Low noise amplifiers in InP technology for pseudo correlating millimeter wave radiometer

This decade will be very important for cosmology due to several missions to measure the cosmic microwave background radiation. These measurements require highly sensitive radiometers operating over a very wide frequency spectrum. The millimeter wave radiometers are best developed as pseudo correlating radiometers due to the inherent stability and high sensitivity of this instrument, To miniaturize the size and power consumption of these radiometers we have developed the critical low noise amplifier and phase switch MMICs using high-performance InP technologies. The low noise amplifiers achieved record 2.3 dB noise figure over the 60-80 GHz frequency band at room temperature and less than 25 K noise temperature at 20 K ambient temperature. These MMICs form the building blocks for 70 GHz highly sensitive correlating radiometers, that are needed e.g. in the ESA Planck mission

Design, development, and verification of the Planck Low Frequency Instrument 70 GHz Front-End and Back-End Modules

Peer reviewe

Endophytes vs tree pathogens and pests: can they be used as biological control agents to improve tree health?

Like all other plants, trees are vulnerable to attack by a multitude of pests and pathogens. Current control measures for many of these diseases are limited and relatively ineffective. Several methods, including the use of conventional synthetic agro-chemicals, are employed to reduce the impact of pests and diseases. However, because of mounting concerns about adverse effects on the environment and a variety of economic reasons, this limited management of tree diseases by chemical methods is losing ground. The use of biological control, as a more environmentally friendly alternative, is becoming increasingly popular in plant protection. This can include the deployment of soil inoculants and foliar sprays, but the increased knowledge of microbial ecology in the phytosphere, in particular phylloplane microbes and endophytes, has stimulated new thinking for biocontrol approaches. Endophytes are microbes that live within plant tissues. As such, they hold potential as biocontrol agents against plant diseases because they are able to colonize the same ecological niche favoured by many invading pathogens. However, the development and exploitation of endophytes as biocontrol agents will have to overcome numerous challenges. The optimization and improvement of strategies employed in endophyte research can contribute towards discovering effective and competent biocontrol agents. The impact of environment and plant genotype on selecting potentially beneficial and exploitable endophytes for biocontrol is poorly understood. How endophytes synergise or antagonise one another is also an important factor. This review focusses on recent research addressing the biocontrol of plant diseases and pests using endophytic fungi and bacteria, alongside the challenges and limitations encountered and how these can be overcome. We frame this review in the context of tree pests and diseases, since trees are arguably the most difficult plant species to study, work on and manage, yet they represent one of the most important organisms on Earth

Endophytes vs tree pathogens and pests: can they be used as biological control agents to improve tree health?

Like all other plants, trees are vulnerable to attack by a multitude of pests and pathogens. Current control measures for many of these diseases are limited and relatively ineffective. Several methods, including the use of conventional synthetic agro-chemicals, are employed to reduce the impact of pests and diseases. However, because of mounting concerns about adverse effects on the environment and a variety of economic reasons, this limited management of tree diseases by chemical methods is losing ground. The use of biological control, as a more environmentally friendly alternative, is becoming increasingly popular in plant protection. This can include the deployment of soil inoculants and foliar sprays, but the increased knowledge of microbial ecology in the phytosphere, in particular phylloplane microbes and endophytes, has stimulated new thinking for biocontrol approaches. Endophytes are microbes that live within plant tissues. As such, they hold potential as biocontrol agents against plant diseases because they are able to colonize the same ecological niche favoured by many invading pathogens. However, the development and exploitation of endophytes as biocontrol agents will have to overcome numerous challenges. The optimization and improvement of strategies employed in endophyte research can contribute towards discovering effective and competent biocontrol agents. The impact of environment and plant genotype on selecting potentially beneficial and exploitable endophytes for biocontrol is poorly understood. How endophytes synergise or antagonise one another is also an important factor. This review focusses on recent research addressing the biocontrol of plant diseases and pests using endophytic fungi and bacteria, alongside the challenges and limitations encountered and how these can be overcome. We frame this review in the context of tree pests and diseases, since trees are arguably the most difficult plant species to study, work on and manage, yet they represent one of the most important organisms on Earth

TRY plant trait database – enhanced coverage and open access

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

State of the world’s plants and fungi 2020

Kew’s State of the World’s Plants and Fungi project provides assessments of our current knowledge of the diversity of plants and fungi on Earth, the global threats that they face, and the policies to safeguard them. Produced in conjunction with an international scientific symposium, Kew’s State of the World’s Plants and Fungi sets an important international standard from which we can annually track trends in the global status of plant and fungal diversity

Planck low frequency instrument (LFI) 70 GHz receiver modules

Elegant Breadboard Model of an ultra low noise 70 GHz continuous comparator total power radiometer with 20 % frequency bandwidth has been built for the ESA Planck Mission. The receiver consists of two separate modules: Front End Module (FEM) and Back-End Module (BEM). The FEM is cooled to 20 K physical temperature while the BEM is operating at room temperature. This continuous comparison receiver is based on use of a structure of similar to a balanced amplifier in the FEM. The FEM LNAs are based on state-of-the-art InP HEMTs processed at NGST (ex. TRW). In addition to this, phase shifters are placed between the FEM hybrids to facilitate DPDT-switching capability. The switching capability is used to remove 1/f noise at the Back-End Module (BEM) amplifier chain. The switching rate is 1 kHz. ehkä More than 35 dB gain and an average 25 K noise temperature was measured at 20 K physical temperature in the Front-End Module (FEM). A 20 dB isolation between the signal and reference channel has been obtained at 20 K physical temperature. A Back-End Module (BEM) having 20 dB RF gain and 20 dB post detection voltage gain has also been built and measured with the FEM.</p

Planck low frequency instrument (LFI) 70 GHz receiver modules

Elegant Breadboard Model of an ultra low noise 70 GHz continuous comparator total power radiometer with 20 % frequency bandwidth has been built for the ESA Planck Mission. The receiver consists of two separate modules: Front End Module (FEM) and Back-End Module (BEM). The FEM is cooled to 20 K physical temperature while the BEM is operating at room temperature. This continuous comparison receiver is based on use of a structure of similar to a balanced amplifier in the FEM. The FEM LNAs are based on state-of-the-art InP HEMTs processed at NGST (ex. TRW). In addition to this, phase shifters are placed between the FEM hybrids to facilitate DPDT-switching capability. The switching capability is used to remove 1/f noise at the Back-End Module (BEM) amplifier chain. The switching rate is 1 kHz. ehkä More than 35 dB gain and an average 25 K noise temperature was measured at 20 K physical temperature in the Front-End Module (FEM). A 20 dB isolation between the signal and reference channel has been obtained at 20 K physical temperature. A Back-End Module (BEM) having 20 dB RF gain and 20 dB post detection voltage gain has also been built and measured with the FEM.</p